"We will reverse all of these anti-people, submissive measures. That is the objective of our movement, of our struggle," he said after filing a criminal complaint with the Attorney General's Office.

The quixotic legal gambit seeks a Senate trial of Peña Nieto for having agreed to "the surrender of oil to foreign oil companies."

The constitutional overhaul promoted by the president will allow private companies to develop Mexico's crude reserves for the first time since the late 1930s, when then-President Lazaro Cardenas nationalized the petroleum industry.

Lopez Obrador, a two-time presidential candidate, said he has evidence that Peña Nieto negotiated the terms of the energy overhaul with private interests in the months between his July 2012 election and his inauguration in December of that year.

"Then they implemented it, using the instruments of control, of manipulation, that belong to this power mafia: those who call themselves the people's representatives ... who are no more than employees of interest groups," the former Mexico City mayor said.

"Here we take the opportunity to remind the owners of Exxon, of Shell, of Chevron, that they will make no profitable deals in our country because the oil is not the government's, not even the state's, much less Peña Nieto's. The oil is the people's and the nation's," Lopez Obrador said.

The criminal complaint against Peña Nieto cites Article 123.1 of the Federal Penal Code, which defines treason as "acts against the independence, sovereignty or integrity of the Mexican nation with the aim of subjecting it to a foreign person, group or government."

"We know - we are not naive - that this Attorney General's Office is at the service of the power mafia, of the band of criminals who are misgoverning our country, but we are fulfilling our responsibility as citizens," Lopez Obrador said.

He has decided to pursue his battle against the energy reform independently of the fight being waged by his former party, the PRD, which is seeking a referendum in 2015 on overturning the measure.

Lopez Obrador said he rejects cooperation with the PRD because the party leaders signed on to Peña Nieto's "Pact for Mexico," an accord the veteran leftist says paved the way for the energy overhaul. EFE